Handheld mobile communication device with flexible keys

ABSTRACT

Keypad keys for handheld mobile communication devices feature flexible key bodies and actuators extending from the key bodies. Switches below the actuators are connected in series circuits. All actuators beneath an intended key must be depressed in order for the circuit to be closed and the key to be recognized as actuated. The flexible nature of the key bodies allows one actuator on a given key to be depressed while other actuators remain non-depressed. This prevents the key from being recognized as actuated when a only a portion of the key is depressed as occurs, for example, due to finger overlap.

FIELD

In general, the present disclosure relates to wireless handheld mobilecommunication devices such as those used to send and receive emailmessages, phone calls or text messages, etc., all of which have come toinclude an alphanumeric keyboard of some sort (e.g., full-scale orreduced key format; QWERTY or other arrangement; etc.). Moreparticularly, the present disclosure relates to a keyboard arrangementfor such devices that is configured to minimize typing errors causedwhen an intended key and an adjacent key are engaged at substantiallythe same time by a user of the device because of finger overlap.

BACKGROUND

A generalized illustration of a wireless handheld mobile communicationdevice is shown in FIG. 1. The device includes a housing, a graphicaldisplay screen, and a keyboard section with a plurality of keys thereon.The device further includes a thumbwheel and one or more navigationaltools such as an auxiliary input device located between the displayscreen and the keyboard section. The auxiliary input device may be anyof a trackball, cursor keys, a track wheel, a roller barrel, a touchpad, or a joystick.

Such wireless handheld mobile communication devices are becoming smallerand smaller for handheld use. In fact, they may be on the order ofbetween fifty millimeters (approximately two inches) and eighty-ninemillimeters (approximately three and one-half inches) in width, tofacilitate palm-cradling of the device by a user. To facilitate suchsmaller device widths, the keys on wireless handheld mobilecommunication devices are being made smaller and smaller. In fact, onsome such devices, the keys may be less than seven millimeters(approximately one quarter of an inch) in width, and as small as threemillimeters (approximately one eighth of an inch) in width. As a result,a user's thumb (or other digit) may overlap several keys at the sametime when the user is trying to depress an intended key on the keyboard,as illustrated in FIG. 1, which leads to typing errors.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a generalized front view of a handheld mobile communicationdevice;

FIG. 2 is an exploded perspective view of a keypad key assembly;

FIG. 3 is an assembled perspective view of a two-actuator keypad keyassembly;

FIG. 4 is an assembled perspective view of a four-actuator keypad keyassembly;

FIG. 5 is a side view of a keypad and keyboard arrangement;

FIG. 6 is an assembly view of a handheld mobile communication device;

FIGS. 7-12 are front views of a handheld mobile communication deviceillustrating auxiliary input devices that are a trackball, cursor keys,a track wheel, a roller barrel, a touch pad, or a joystick,respectively;

FIG. 13 illustrates an exemplary QWERTY keyboard layout;

FIG. 14 illustrates an exemplary QWERTZ keyboard layout;

FIG. 15 illustrates an exemplary AZERTY keyboard layout;

FIG. 16 illustrates an exemplary Dvorak keyboard layout;

FIG. 17 illustrates a QWERTY keyboard layout paired with a traditionalten-key keyboard;

FIG. 18 illustrates ten digits comprising the numerals 0-9 arranged ason a telephone keypad, including the * and # astride the zero;

FIG. 19 illustrates a numeric phone key arrangement according to the ITUStandard E.161 including both numerals and letters;

FIG. 20 is a detail view of a reduced QWERTY keyboard;

FIG. 21 is a detail view of an alternative reduced QWERTY keyboard; and

FIG. 22 is a block diagram illustrating a wireless handheldcommunication device interacting in a communication network.

DETAILED DESCRIPTION

As intimated hereinabove, one of the more important aspects of thehandheld electronic device to which this disclosure is directed is itssize. While some users will grasp the device in both hands, it isintended that a predominance of users will cradle the device in one handin such a manner that input and control over the device can be affectedusing the thumb of the same hand in which the device is held. Thereforethe size of the device must be kept relatively small; of its dimensions,limiting the width of the device is most important with respect toassuring cradleability in a user's hand. Moreover, it is preferred thatthe width of the device be maintained at less than ten centimeters(approximately four inches). Keeping the device within these dimensionallimits provides a hand cradleable unit that users prefer for itsuseability and portability. Limitations with respect to the height(length) of the device are less stringent with importance placed onmaintaining device hand-cradleability. Therefore, in order to gaingreater size, the device can be advantageously configured so that itsheight is greater than its width, but still remain easily supported andoperated in one hand.

A potential problem is presented by the small size of the device in thatthere is limited exterior surface area for the inclusion of user inputand device output features. This is especially true for the “prime realestate” of the front face of the device where it is most advantageous toinclude a display screen that outputs information to the user and whichis preferably above a keyboard utilized for data entry into the deviceby the user. If the screen is provided below the keyboard, a problemoccurs in being able to see the screen while inputting data. Thereforeit is preferred that the display screen be above the input area, therebysolving the problem by assuring that the hands and fingers do not blockthe view of the screen during data entry periods.

To facilitate textual data entry, an alphabetic keyboard is provided. Inone version, a full alphabetic keyboard is utilized in which there isone key per letter. This is preferred by some users because it can bearranged to resemble a standard keyboard with which they are mostfamiliar. In this regard, the associated letters can be advantageouslyorganized in QWERTY, QWERTZ, AZERTY or Dvorak layouts, among others,thereby capitalizing on certain users' familiarity with these specialletter orders. In order to stay within the bounds of a limited frontsurface area, however, each of the keys must be commensurately smallwhen, for example, twenty-six keys must be provided in the instance ofthe English language. An alternative configuration is to provide areduced keyboard in which at least some of the keys have more than oneletter associated therewith. This means that fewer keys can be includedwhich makes it possible for those fewer keys to each be larger than inthe instance when a full keyboard is provided on a similarly dimensioneddevice. Some users will prefer the solution of the larger keys over thesmaller ones, but it is necessary that software or hardware solutions beprovided in order to discriminate which of the several associatedletters the user intends based on a particular key actuation; a problemthe full keyboard avoids. Preferably, this character discrimination isaccomplished utilizing disambiguation software accommodated within thedevice. As with the other software programs embodied within the device,a memory and microprocessor are provided within the body of the handheldunit for receiving, storing, processing, and outputting data during use.Therefore, the problem of needing a textual data input means is solvedby the provision of either a full or reduced alphabetic keyboard on thepresently disclosed handheld electronic device.

Keys, typically of a push-button or push-pad nature, perform well asdata entry devices but present problems to the user when they must alsobe used to affect navigational control over a screen-cursor. In order tosolve this problem the present handheld electronic device preferablyincludes an auxiliary input that acts as a cursor navigational tool andwhich is also exteriorly located upon the front face of the device. Itsfront face location is particularly advantageous because it makes thetool easily thumb-actuable like the keys of the keyboard. A particularlyusable embodiment provides the navigational tool in the form of atrackball which is easily utilized to instruct two-dimensional screencursor movement in substantially any direction, as well as act as anactuator when the ball of the trackball is depressible like a button.The placement of the trackball is preferably above the keyboard andbelow the display screen; here, it avoids interference duringkeyboarding and does not block the user's view of the display screenduring use.

In some configurations, the handheld electronic device may be standalonein that it is not connectable to the “outside world.” One example wouldbe a PDA that stores such things as calendars and contact information,but is not capable of synchronizing or communicating with other devices.In most situations such isolation will be detrimentally viewed in thatat least synchronization is a highly desired characteristic of handhelddevices today. Moreover, the utility of the device is significantlyenhanced when connectable within a system, and particularly whenconnectable on a wireless basis in a system in which both voice and textmessaging are accommodated.

It should be appreciated at the outset that while the instant disclosuredescribes one or more preferred embodiments of a keyboard, variouslyconfigured as described above, such embodiments are presented solely forpurposes of illustration and the scope of the appended claims is notintended to be limited to the specific embodiments described in theinstant disclosure or illustrated in the attached figures.

The instant disclosure relates to handheld electronic devices and moreparticularly to mobile handheld communication devices comprisingkeyboards. As used herein, the term “handheld electronic device”describes a relatively small electronic device that is capable of beingheld in a user's hand. “Handheld electronic device” is a broad term thatincludes devices further classified as handheld communication devices,and mobile handheld communications devices, which can interact with oneor more communications networks to transmit and receive data of varioustypes, e.g., text, voice, data, etc.

As may be appreciated from FIG. 6, the handheld electronic device 300comprises a lighted display 322 located above a keyboard 332 suitablefor accommodating textual input to the handheld electronic device 300when in an operable configuration. Preferably, the display screen 322and keyboard 332 are located at the front face of the handheldelectronic device 300. As shown, the device 300 is of unibodyconstruction, but it is also contemplated that the device may be of analternative construction such as that commonly known as “clamshell” or“flip-phone” style. Regardless, in operable configuration for the device300, the navigation tool (auxiliary input) 328 is located essentiallybetween the display 322 and the keyboard 332.

The keyboard disclosed herein can be a full keyboard. A full keyboardrefers to a keyboard on which all the keys of the alphabet are shown asindicia on the keys. Reference to a full keyboard in the remainder ofthe disclosure can be abbreviated as “keyboard.” The format of theindicia shown on the keys can comprise, for example, the letters A-Z inone of a standard keyboard layout and/or numerals as described later inthis writing. Examples of different types of standard keyboard layoutsinclude, but are not limited to: QWERTY, QWERTZ, AZERTY, and Dvoraklayouts. In the embodiments disclosed, the keyboard is secured to thehousing and the keys are located on the face side of the device.

In the alternative to comprising a full keyboard, the keyboard can beconfigured to comprise a plurality of keys wherein alphabetic lettersare associated with the keys, but at least a portion of the individualkeys have multiple alphabetic letters associated therewith. This type ofconfiguration is referred to as a reduced keyboard (in comparison to thefull keyboard described immediately above) and can, among otherscomprise QWERTY, QWERTZ, AZERTY, and Dvorak layouts.

A wireless handheld mobile electronic device according to the presentdisclosure may have an overall or general configuration like that shownin FIG. 1, or it may have another configuration as may be desired. Thekeys and keyboard of a device according to the present disclosure,however, are as described below.

In particular, a keypad arrangement and keypad key 200 are illustratedin FIGS. 2 through 5. Each key 200 in the keypad arrangement may have agenerally rectangular key body 202 and a pair of peg actuators 204extending downward from the undersurface of the key body 202, i.e.,toward the support frame face 205 on which the keys 200 are mounted. Asillustrated in FIG. 4, four peg actuators 204 can also extend downwardfrom the undersurface of the key body 202, i.e., toward the supportframe face 205. Four peg actuators 204 would be used in instances wherethe keys 200 are especially small and thus more likely to induce fingeroverlap. In such situations, using four peg actuators 204, as opposed totwo peg actuators 204, would be optimal as four peg actuators 204 wouldrequire the user to make squarer contact with the intended key 200 andthus reduce the likelihood of inadvertent key 200 depression from fingeroverlap. The major portion of the key body 202 is made from a flexibleplastic material but the portions 206 of the key body 202 by means ofwhich the actuators 204 are interconnected to the key body 202 areharder/stiffer than the flexible portion of the key body 202. In theillustrated embodiment 200, the actuators 204 are located at diagonallyopposite corners of the rectangular key body 202, which is 180° (i.e.,360° divided by the number of actuators 204) circumferentially apartfrom each other about a centerpoint of the key body 202.

For each keyboard key 200, there is a set of closeable switches 208,e.g., dome switches, resistive switches, or capacitive switches, mountedon the support frame face 205 and connected together in a series circuit210 that connects to the device's processor 338. The number of closeableswitches 208 associated with each key 200 is the same as the number ofactuators 204 and the closeable switches 208 are connected to theactuators 204. Furthermore, the closeable switches 208 associated witheach actuator 204 also bias the keyboard key 200 away from the supportframe face 205 toward an unactuated position. (It will be understoodthat the device housing retains the keypad keys in their respectivepositions.)

In another embodiment, centered under each keyboard key 200 is acloseable switch 208 mounted on the support frame face 205. Connected tothis centered closeable switch 208 is a centrally located actuator 204that extends downward from the central undersurface of the key body 202.Two or four opposing actuators 204, located at diagonally oppositecorners of the rectangular key body 202, are provided peripherally aboutthe central actuator 204 beneath the keyboard key 200. The peripheralactuators 204 effectively surround the centered closeable switch 208 andare connected together in a series circuit 201 that connects to thedevice's processor 338—the central actuator 204 may or may not beconnected to this series circuit 201. However, the actuators 204 alongthe periphery do not provide tactile feedback to the user—only thecentered closeable switch 208 and actuator 204 provide tactile feedbackto the user. The four peripheral actuators 204—are connected to the lessflexible portions 206 of the key body 202 while the central actuator 204is connected to the more flexible plastic material comprising the majorportion of the key body 202.

The configuration of the keypad keys 200 and the associated seriescircuit 210 arrangement of the closeable switches 208 helps prevent orminimize typing errors due to finger overlap of multiple keys bynecessitating that all actuator interconnect portions 206 on the keypadkey body 202 be depressed in order for a key 200 to be recognized asactuated. For example, as illustrated in FIG. 5, the central key 220 isthe key the user intends to depress with his or her thumb 221. The thumb221 covers the entire face 203 of the key body 202 of the intended key220, and therefore both actuators 204 of that key 220 are depressed,thereby closing both associated switches 208 and completing theassociated series circuit 210 such that the intended key 220 isrecognized as actuated by the device's processor 338. As furtherillustrated, however, the user's thumb 221 extends beyond the intendedkey 220 and partially overlaps an adjacent key, e.g., unintended key222. However, because the mid portion of the key body 202 is flexible,the actuator 204 under the tip of the user's thumb 221 may be depressedand its associated switch 208 closed, but the other actuator 204associated with the key 222 remains in its non-depressed or unactuatedposition. As a result, the switch 208 associated with that actuator 204will remain open, hence leaving the series circuit 210 associated withthe unintended key 222 open, and the processor 338 will not recognizethe unintended key 222 as having been depressed.

As illustrated more clearly in FIGS. 7 through 12, respectively, thenavigation controller assembly 328 can comprise several forms thatinclude, but are not limited to: a trackball 121, cursor keys 122, atrack wheel 141, a roller barrel 151, a touch pad 161, or a joystick171. The location of the trackball 121, cursor keys 122, roller barrel151, touch pad 161, or joystick 171 between the display 322 of thehandheld communication device 300 and the keyboard 332 provides the userwith a familiar location for the navigation controller assembly 328.Similarly, the location of the track wheel 141 on the side of the device300 also provides the user with a familiar location for the navigationcontroller assembly 328.

The various characters, commands and functions associated with keyboardtyping, in general, are traditionally arranged using variousconventions. The most common of these in the United States, forinstance, is the QWERTY keyboard layout. Others include the QWERTZ,AZERTY, and Dvorak keyboard configurations of the English languagealphabet.

The QWERTY keyboard layout is the standard English-language alphabetickey arrangement 44 and is exemplified in FIG. 13. In this configuration,Q, W, E, R, T and Y are the letters on the top left, alphabetic row. Itwas designed by Christopher Sholes, who invented the typewriter. Thekeyboard layout was organized by him to prevent people from typing toofast and jamming the keys. The QWERTY layout was included in the drawingfor Sholes' patent application in 1878.

The QWERTZ keyboard layout is normally used in German-speaking regions.This alphabetic key arrangement 44 is shown in FIG. 14. In thisconfiguration, Q, W, E, R, T and Z are the letters on the top left,alphabetic row. It differs from the QWERTY keyboard layout by exchangingthe “Y” with a “Z”. This is because “Z” is a much more common letterthan “Y” in German and the letters “T” and “Z” often appear next to eachother in the German language.

The AZERTY keyboard layout is normally used in French-speaking regions.This alphabetic key arrangement 44 is shown in FIG. 15. In thisconfiguration, A, Z, E, R, T and Y are the letters on the top left,alphabetic row. It is similar to the QWERTY layout, except that theletters Q and A are swapped, the letters Z and W are swapped, and theletter M is in the middle row instead of the bottom one.

The Dvorak keyboard layout was designed in the 1930s by August Dvorakand William Dealey. This alphabetic key arrangement 44 is shown in FIG.16. It was developed to allow a typist to type faster. About 70% ofwords are typed on the home row compared to about 32% with a QWERTYkeyboard layout, and more words are typed using both hands. It is saidthat in eight hours, fingers of a QWERTY typist travel about 16 miles,but only about 1 mile for the Dvorak typist.

Alphabetic key arrangements in full keyboards and typewriters are oftenpresented along with numeric key arrangements. Exemplary numeric keyarrangements are shown in FIGS. 13-16 wherein the numbers 1-9 and 0 arepositioned above the alphabetic keys. In another numeric keyarrangement, numbers share keys with the alphabetic characters, such asfor example, the top row of the QWERTY keyboard (not shown). Yet anotherexemplary numeric key arrangement is shown in FIG. 17, where a numerickeypad 46 is spaced from the alphabetic/numeric key arrangement. Thenumeric keypad 46 includes the numbers “7”, “8”, “9” arranged in a toprow, “4”, “5”, “6” arranged in a second row, “1”, “2”, “3” arranged in athird row, and “0” in a bottom row, consistent with what may be found ona “ten-key” computer keyboard keypad. Additionally, a numeric phone keyarrangement 42 is shown in FIGS. 18 and 19.

As shown in FIG. 18, the numeric phone key arrangement 42 may alsoutilize a surface treatment on the surface of the center “5” key. Thissurface treatment is such that the surface of the key is distinctivefrom the surface of other keys. Preferably the surface treatment is inthe form of a raised bump or recessed dimple 43. This bump or dimple 43is typically standard on telephones and is used to identify the “5” keythrough touch alone. Once the user has identified the “5” key, it ispossible to identify the remainder of the phone keys through touch alonebecause of their standard placement. The bump or dimple 43 preferablyhas a shape and size that is readily evident to a user through touch. Anexample bump or dimple 43 may be round, rectangular, or have anothershape if desired. Alternatively, raised bumps may be positioned on thehousing around the “5” key and do not necessarily have to be positioneddirectly on the key, as known by those of skill in the art.

It is desirable for handheld electronic devices 300 to include acombined text-entry keyboard and a telephony keyboard. Examples of suchmobile communication devices include mobile stations, cellulartelephones, wireless personal digital assistants (PDAs), two-way pagingdevices, and others. Various keyboards are used with such devicesdepending in part on the physical size of the handheld electronicdevice. Some of these are termed full keyboard, reduced keyboard, andphone key pads.

In embodiments of the handheld electronic device 300 having a fullkeyboard, only one alphabetic character is associated with each one of aplurality of physical keys. Thus, with an English-language keyboard,there are at least 26 keys in the plurality, one for each letter of theEnglish alphabet. In such embodiments using the English-languagealphabet, one of the keyboard layouts described above is usuallyemployed, and with the QWERTY keyboard layout being the most common.

Other embodiments can comprise a full keyboard for alphabetic charactersand incorporate a combined numeric keyboard. In this embodiment, numericcharacters share keys with alphabetic characters on the top row of theQWERTY keyboard (not shown).

In order to further reduce the size of the handheld electronic device300 without making the physical keys or software keys too small, thehandheld electronic device 300 can be configured to comprise a reducedkeyboard, where more than one character/command/function is associatedwith each of at least a portion of the plurality of keys. Consequently,certain keys can be ambiguous since more than one character isrepresented by, or associated with, a particular key even though onlyone of those characters is typically intended by the user whenactivating the key. The reduced key arrangement is exemplified withinFIGS. 20 and 21.

A reduced key arrangement 332 is presented in FIG. 20. Fourteen keys onthe keyboard 332 are associated with alphabetic characters and ten keysare associated with numbers. The four rows include a first row 50, asecond row 52, a third row 54, and a fourth row 56. The five columnsinclude a first column 60, a second column 62, a third column 64, afourth column 66, and a fifth column 68. Many of the keys have differentsizes than the other keys, and the rows are non-linear. In particular,the rows are V-shaped, with the middle key in the third column 64representing the point of the V. The columns are generally straight, butthe outer two columns 60, 62, 66, 68 angle inwardly toward the middlecolumn 64. To readily identify the phone user interface (the second userinterface), the numeric phone keys 0-9 include a color scheme that isdifferent from that of the remaining keys associated with the QWERTY keyarrangement.

In this example, the color scheme of the numeric phone keys has a twotone appearance, with the upper portion of the numeric keys being afirst color and the lower portion of the numeric keys being a secondcolor. In the example, the upper portion of the keys is white with blueletters and the lower portion of the keys is blue with white letters.Most of the remaining keys associated with the QWERTY key arrangementare predominantly the second, blue color with white lettering. The firstcolor may be lighter than the second color, or darker than the secondcolor. In addition, the keyboard 332 includes a “send” key 6 and an“end” key 8. The “send” key 6 is positioned in the upper left corner ofthe keyboard 332 and the “end” key 8 is positioned in the upper rightcorner. The “send” key 6 and “end” key 8 may have different colorschemes than the remainder of the keys in order to distinguish them fromother keys. In addition, the “send” and “end” keys 6, 8 may havedifferent colors from one another. In the example shown, the “send” key6 is green and the “end” key 8 is red. Different colors may be utilized,if desired.

FIG. 21 shows a similar format for the reduced QWERTY arrangement ofalphabetic characters 44, but the numeric phone key arrangement 42 ispositioned in the first 60, second 62, and third 64 columns instead ofbeing centered on the keyboard 332. The first row 50 of keys includes inorder the following key combinations for the text entry and telephonymode: “QW/1”, “ER/2”, “TY/3”, “UI”, and “OP”. The second row 52 includesthe following key combinations in order: “AS/4”, “DF/5”, “GH/6”, “JK/,”,and “L/.”. The third row 54 includes the following key combinations inorder: “ZX/7”, “CV/8”, “BN/9”, “M/sym” and “backspace/delete”. Thefourth row 56 includes the following key combinations in order:“next/*”, “space/0”, “shift/#”, “alt” and “return/enter”. The keys ineach of the rows are of uniform size and the rows and columns arestraight

Thus, the processor 338 of the handheld electronic device 300 can beprogrammed with software to determine or predict what letter or word hasbeen intended by the user. Predictive text technologies can alsoautomatically correct common spelling errors. Predictive textmethodologies often include a disambiguation engine and/or a predictiveeditor application. This helps facilitate easy spelling and composition,since the software is preferably intuitive software with a large wordlist and the ability to increase that list based on the frequency ofword usage. The software preferably also has the ability to recognizecharacter letter sequences that are common to the particular language,such as, in the case of English, words ending in “ing.” Such systems canalso “learn” the typing style of the user making note of frequently usedwords to increase the predictive aspect of the software. With predictiveeditor applications, the display of the device depicts possiblecharacter sequences corresponding to the keystrokes that were entered.Typically, the most commonly used word is displayed first. The user mayselect other, less common words manually, or otherwise. Other types ofpredictive text computer programs may be utilized with the keyboardarrangement and keyboard described herein, without limitation.

The multi-tap method of character selection has been in use a number ofyears for permitting users to enter text using a touch screen device ora conventional telephone keypad such as specified under ITU E 1.161,among other devices. Multi-tap requires a user to press a key a varyingnumber of times, generally within a limited period of time, to input aspecific letter, thereby spelling the desired words of the message. Arelated method is the long tap method, where a user depresses the keyuntil the desired character appears on the display out of a rotatingseries of letters.

A “text on nine keys” type system uses predictive letter patterns toallow a user to ideally press each key representing a letter only onceto enter text. Unlike multi-tap which requires a user to indicate adesired character by a precise number of presses of a key, orkeystrokes, the “text on nine key” system uses a predictive textdictionary and established letter patterns for a language tointelligently guess which one of many characters represented by a keythat the user intended to enter. The predictive text dictionary isprimarily a list of words, acronyms, abbreviations and the like that canbe used in the composition of text.

Generally, all possible character string permutations represented by anumber of keystrokes entered by a user are compared to the words in thepredictive text dictionary and a subset of the permutations is shown tothe user to allow selection of the intended character string. Thepermutations are generally sorted by likelihood of occurrence which isdetermined from the number of words matched in the predictive textdictionary and various metrics maintained for these words. Where thepossible character string permutations do not match any words in thepredictive text dictionary, the set of established letter patterns for aselected language can be applied to suggest the most likely characterstring permutations, and then require the user to input a number ofadditional keystrokes in order to enter the desired word.

The keys of reduced keyboards are laid out with various arrangements ofcharacters, commands and functions associated therewith. In regards toalphabetic characters, the different keyboard layouts identified aboveare selectively used based on a user's preference and familiarity; forexample, the QWERTY keyboard layout is most often used by Englishspeakers who have become accustomed to the key arrangement.

Further aspects of the environments, devices and methods of employmentdescribed hereinabove are expanded upon in the following details. Anexemplary embodiment of the handheld electronic device 300 is shown inFIGS. 1, 7-12 and is cradleable in the palm of a user's hand. The sizeof the device 300 is such that a user is capable of operating the device300 using the same hand that is holding the device 300. In anembodiment, the user is capable of actuating all features of the device300 using a single thumb of the cradling hand. In another embodiment,the handheld device 300 features a keyboard 332 on the face of thedevice 300, and the keyboard 332 is actuable by the thumb of the handcradling the device 300. The user may also hold the device 300 in such amanner to enable two thumbs to type on the device 300. Furthermore, theuser may use fingers rather than thumbs to actuate the keyson the device300. In order to accommodate palm-cradling of the device 300 by theaverage person, the length, or height, of the device 300 is generallygreater than the width, and the width is preferably betweenapproximately fifty and seventy-six millimeters (approximately two andthree inches), but by no means limited to such dimensions.

The handheld electronic device 300 includes an input portion and anoutput display portion. The output display portion can be a displayscreen 322, such as an LCD or other similar display device.

The input portion includes a plurality of keys that can be of a physicalnature such as actuable buttons. Each key of the plurality of keys hasat least one actuable action which can be the input of a character, acommand or a function. In this context, “characters” are contemplated toexemplarily include alphabetic letters, language symbols, numbers,punctuation, insignias, icons, pictures, and even a blank space. Inputcommands and functions can include such things as delete, backspace,moving a cursor up, down, left or right, initiating an arithmeticfunction or command, initiating a command or function specific to anapplication program or feature in use, initiating a command or functionprogrammed by the user and other such commands and functions that arewell known to those persons skilled in the art. Specific keys or othertypes of input devices can be used to navigate through the variousapplications and features thereof. Further, depending on the applicationor feature in use, specific keys can be enabled or disabled.

All or a portion of the plurality of keys have one or more indiciadisplayed at their top surface and/or on the surface of the areaadjacent the respective key, the particular indicia representing thecharacter(s), command(s) and/or function(s) typically associated withthat key. In the instance where the indicia of a key's function isprovided adjacent the key, it is understood that this may be a permanentinsignia that is, for instance, printed on the device cover beside thekey, or in the instance of keys located adjacent the display screen, acurrent indicia for the key may be temporarily shown nearby the key onthe screen.

Physical and software keys can be combined in many different ways asappreciated by those skilled in the art. In one embodiment, physical andsoftware keys are combined such that the plurality of enabled keys for aparticular application or feature of the handheld electronic device 300is shown on the display screen 322 in the same configuration as thephysical keys. Thus, the desired character, command or function isobtained by depressing the physical key corresponding to the character,command or function displayed at a corresponding position on the displayscreen, rather than touching the display screen 322. To aid the user,indicia for the characters, commands and/or functions most frequentlyused are preferably positioned on the physical keys and/or on the areaaround or between the physical keys. In this manner, the user can morereadily associate the correct physical key with the character, commandor function displayed on the display screen 322.

An exemplary handheld electronic device 300 is shown in the assemblydrawing of FIG. 6 and its cooperation in a wireless network isexemplified in the block diagram of FIG. 22. These figures are exemplaryonly, and those persons skilled in the art will appreciate theadditional elements and modifications necessary to make the device workin particular network environments.

FIG. 6 is an exploded view showing some of the typical components foundin the assembly of the handheld electronic device 300. The constructionof the device benefits from various manufacturing simplifications. Theinternal components are constructed on a single PCB (printed circuitboard) 102. The support frame 101 holds the keyboard 332 and cursornavigation assembly 328 in place above the PCB 102. The support frame101 also provides an attachment point for the display (not shown). Alens 103 can cover the display to prevent damage. When assembled, thesupport frame 101 and the PCB 102 are fixedly attached to each other andthe display 322 is positioned between the PCB 102 and support frame 101.

A serial port (preferably a Universal Serial Bus port) 330 and anearphone jack 140 can be fixedly attached to the PCB 102 and furtherheld in place by right side element 105. Buttons 130, 131, 132, 133 canbe attached to switches (not shown), which are connected to the PCB 102.

Final assembly can involve placing the top piece 107 and bottom piece108 in contact with support frame 101. Furthermore, the assembly caninterconnect right side element 105 and left side element 106 with thesupport frame 101, PCB 102, and lens 103. These side elements 105, 106can provide additional protection and strength to the support structureof the device 300. In an embodiment, backplate 104 can be removablyattached to the other elements of the device. As it may be appreciatedby those having skill in the art, handheld electronic device 300 may bedifferently configured than the embodiment illustrated in FIG. 6 suchthat components and methods of assembly therefore, can vary

The block diagram of FIG. 22, represents an embodiment of handheldelectronic device 300 interacting in a communications network 319, andillustrates the use of a microprocessor 338 to control operation of thedevice 300. In FIG. 22, communication subsystem 311 performs allcommunication transmission and reception with wireless network 319. Themicroprocessor 338 further connects with an auxiliary input/output (I/O)subsystem 328, a serial port (preferably a Universal Serial Bus port)330, a display 322, a keyboard 332, a speaker 334, a microphone 336,random access memory (RAM) 326, and flash memory 324. Othercommunications subsystems 340 and other device subsystems 342 aregenerally indicated as connected to the microprocessor 338 as well. Anexample of a communication subsystem 340 is that of a short rangecommunication subsystem such as BLUETOOTH® communication module or aninfrared device and associated circuits and components. Additionally,the microprocessor 338 is capable of performing operating systemfunctions and can enable execution of software applications on thecommunication device 300.

The above described auxiliary I/O subsystem 328 can take a variety ofdifferent subsystems including the above described cursor navigationassembly. Other auxiliary I/O devices can include external displaydevices and externally connected keyboards (not shown). While the aboveexamples have been provided in relation to the auxiliary I/O subsystem328, other subsystems capable of providing input or receiving outputfrom the handheld electronic device 300 are considered within the scopeof this disclosure.

In a preferred embodiment, the handheld electronic device 300 isdesigned to wirelessly connect with a communication network 319. Somecommunication networks that the handheld electronic device 300 may bedesigned to operate on require a subscriber identity module (SIM) orremovable user identity module (RUIM). Thus, a device 300 intended tooperate on such a system will include SIM/RUIM interface 344 into whichthe SIM/RUIM card (not shown) may be placed. The SIM/RUIM interface 344can be one in which the SIM/RUIM card is inserted and ejected.

In an exemplary embodiment, a flash memory 324 is enabled to provide astorage location for the operating system, device programs, and data.While the operating system in a preferred embodiment is stored in flashmemory 324, the operating system in other embodiments is stored inread-only memory (ROM) or similar storage element (not shown). As thoseskilled in the art will appreciate, the operating system, deviceapplication or parts thereof may be loaded in RAM 326 or other volatilememory.

In a preferred embodiment, the flash memory 324 containsprograms/applications 358 for execution on the device 300 including anaddress book 352, a personal information manager (PIM) 354, and thedevice state 350. Furthermore, programs 358 and other information 356can be segregated upon storage in the flash memory 324 of the device300. However, another embodiment of the flash memory 324 utilizes astorage allocation method such that a program 358 is allocatedadditional space in order to store data associated with such program.Other known allocation methods exist in the art and those personsskilled in the art will appreciate additional ways to allocate thememory of the device 300.

In a preferred embodiment, the device 300 is pre-loaded with a limitedset of programs that enable it to operate on the communication network319. Another program that can be preloaded is a PIM 354 application thathas the ability to organize and manage data items including but notlimited to email, calendar events, voice messages, appointments and taskitems. In order to operate efficiently, memory 324 is allocated for useby the PIM 354 for the storage of associated data. In a preferredembodiment, the information that PIM 354 manages is seamlesslyintegrated, synchronized and updated through the communication network319 with a user's corresponding information on a remote computer (notshown). The synchronization, in another embodiment, can also beperformed through the serial port 330 or other short range communicationsubsystem 340. Other applications may be installed through connectionwith the wireless network 319, serial port 330 or via other short rangecommunication subsystems 340.

When the device 300 is enabled for two-way communication within thewireless communication network 319, it can send and receive signals froma mobile communication service. Examples of communication systemsenabled for two-way communication include, but are not limited to, theMOBITEX mobile communication system, DATATAC mobile communicationsystem, the GPRS (General Packet Radio Service) network, the UMTS(Universal Mobile Telecommunication Service) network, the EDGE (EnhancedData for Global Evolution) network, and the CDMA (Code Division MultipleAccess) network and those networks generally described aspacket-switched, narrowband, data-only technologies mainly used forshort burst wireless data transfer.

For the systems listed above, the communication device 300 must beproperly enabled to transmit and receive signals from the communicationnetwork 319. Other systems may not require such identifying information.GPRS, UMTS, and EDGE require the use of a SIM (Subscriber IdentityModule) in order to allow communication with the communication network319. Likewise, most CDMA systems require the use of a RUIM (RemovableIdentity Module) in order to communicate with the CDMA network. The RUIMand SIM card can be used in multiple different handheld electronicdevices 300. Handheld electronic device 300 can be configured to operatesome features without a SIM/RUIM card, but it may not be able tocommunicate with the network 319. In some locations, the handheldelectronic device 300 can be enabled to work with special services, suchas “911” emergency, without a SIM/RUIM or with a non-functioningSIM/RUIM card. A SIM/RUIM interface 344 located within the device allowsfor removal or insertion of a SIM/RUIM card (not shown). This interface344 can be configured like that of a disk drive or a PCMCIA slot orother known attachment mechanism in the art. The SIM/RUIM card featuresmemory and holds key configurations 351, and other information 353 suchas identification and subscriber related information. Furthermore, aSIM/RUIM card can be enabled to store information about the userincluding identification, carrier and address book information. With aproperly enabled handheld electronic communications device 300, two-waycommunication between the handheld electronic device 300 andcommunication network 319 is possible.

If the handheld electronic device 300 is enabled as described above orthe communication network 319 does not require such enablement, thetwo-way communication enabled device 300 is able to both transmit andreceive information from the communication network 319. The transfer ofcommunication can be from the device 300 or to the device 300. In orderto communicate with the communication network 319, the device 300 in apreferred embodiment is equipped with an integral or internal antenna318 for transmitting signals to the communication network 319. Likewisethe communication device 300 in the preferred embodiment is equippedwith another antenna 316 for receiving communication from thecommunication network 319. These antennae 316, 318 in another preferredembodiment are combined into a single antenna (not shown). As oneskilled in the art would appreciate, the antenna or antennae 316, 318 inanother embodiment are externally mounted on the device 300.

When equipped for two-way communication, the handheld electronic device300 features a communication subsystem 311. As is well known in the art,this communication subsystem 311 is modified so that it can support theoperational needs of the device 300. The subsystem 311 includes atransmitter 314 and receiver 312 including the associated antenna orantennae 316, 318 as described above, local oscillators (LOs) 313, and aprocessing module 320 which in a preferred embodiment is a digitalsignal processor (DSP) 320.

A signal received by the wireless handheld electronic device 300 isfirst received by the antenna 316 and then input into a receiver 312,which in a preferred embodiment is capable of performing common receiverfunctions including signal amplification, frequency down conversion,filtering, channel selection and the like, and analog to digital (A/D)conversion. The A/D conversion allows the DSP 320 to perform morecomplex communication functions such as demodulation and decoding on thesignals that are received by DSP 320 from the receiver 312. The DSP 320is also capable of issuing control commands to the receiver 312. Anexample of a control command that the DSP 320 is capable of sending tothe receiver 312 is gain control, which is implemented in automatic gaincontrol algorithms implemented in the DSP 320. Likewise, thecommunication device 300 is capable of transmitting signals to thecommunication network 319. The DSP 320 communicates the signals to besent to the transmitter 314 and further communicates control functions,such as the above described gain control. The signal is emitted by thedevice 300 through an antenna 318 connected to the transmitter 314.

It is contemplated that communication by the device 300 with thewireless network 319 can be any type of communication that both thewireless network 319 and device 300 are enabled to transmit, receive andprocess. In general, these can be classified as voice and data. Voicecommunication is communication in which signals for audible sounds aretransmitted by the device 300 through the communication network 319.Data is all other types of communication that the device 300 is capableof performing within the constraints of the wireless network 319.

In the instance of voice communications, voice transmissions thatoriginate from the communication device 300 enter the device 300 thougha microphone 336. The microphone 336 communicates the signals to themicroprocessor 338 for further conditioning and processing. Themicroprocessor 338 sends the signals to the DSP 320 which controls thetransmitter 314 and provides the correct signals to the transmitter 314.Then, the transmitter 314 sends the signals to the antenna 318, whichemits the signals to be detected by a communication network 319.Likewise, when the receiver 312 obtains a signal from the receivingantenna 316 that is a voice signal, it is transmitted to the DSP 320which further sends the signal to the microprocessor 338. Then, themicroprocessor 338 provides a signal to the speaker 334 of the device300 and the user can hear the voice communication that has beenreceived. The device 300 in a preferred embodiment is enabled to allowfor full duplex voice transmission.

In another embodiment, the voice transmission may be received by thecommunication device 300 and translated as text to be shown on thedisplay screen 322 of the communication device 300. The communicationdevice 300 is also capable of retrieving messages from a voice messagingservice operated by the communication network operator. In a preferredembodiment, the device 300 displays information in relation to the voicemessage, such as the number of voice messages or an indication that anew voice message is present on the operating system.

In a preferred embodiment, the display 322 of the communication device300 provides an indication about the identity of an incoming call,duration of the voice communication, telephone number of thecommunication device, call history, and other related information. Itshould be appreciated that the above described embodiments are given asexamples only and one skilled in the art may effect alterations,modifications and variations to the particular embodiments withoutdeparting from the scope of the application.

As stated above, the communication device 300 and communication network319 can be enabled to transmit, receive and process data. Severaldifferent types of data exist and some of these types of data will bedescribed in further detail. One type of data communication that occursover the communication network 319 includes electronic mail (email)messages. Typically an email is text based, but can also include othertypes of data such as picture files, attachments and html. While theseare given as examples, other types of messages are considered within thescope of this disclosure as well.

When the email originates from a source outside of the device and iscommunicated to the device 300, it is first received by the receivingantenna 316 and then transmitted to the receiver 312. From the receiver312, the email message is further processed by the DSP 320, and it thenreaches the microprocessor 338. The microprocessor 338 executesinstructions as indicated from the relevant programming instructions todisplay, store or process the email message as directed by the program.In a similar manner, once an email message has been properly processedby the microprocessor 338 for transmission to the communication network319, it is first sent to the DSP 320, which further transmits the emailmessage to the transmitter 314. The transmitter 314 processes the emailmessage and transmits it to the transmission antenna 318, whichbroadcasts a signal to be received by a communication network 319. Whilethe above has been described generally, those skilled in this art willappreciate those modifications which are necessary to enable thecommunication device 300 to properly transmit the email message over agiven communication network 319.

Furthermore, the email message may instead be transmitted from thedevice 300 via a serial port 330, another communication port 340, orother wireless communication ports 340. The user of the device 300 cangenerate a message to be sent using the keyboard 332 and/or auxiliaryI/O 328, and the associated application to generate the email message.Once the email message is generated, the user may execute a send commandwhich directs the email message from the communication device 300 to thecommunication network 319. In an exemplary embodiment, a keyboard 332,and preferably an alphanumeric keyboard is used to compose the emailmessage. In a preferred embodiment, an auxiliary I/O device 328 is usedin addition to the keyboard 332.

While the above has been described in relation to email messages, oneskilled in the art can modify the procedures to function with othertypes of data such as SMS text messages, internet websites, videos,instant messages, programs and ringtones. Once the data is received bythe microprocessor 338, the data is placed appropriately within theoperating system of the device 300. This might involve presenting amessage on the display 322 which indicates the data has been received orstoring it in the appropriate memory 324 on the device 300. For example,a downloaded application such as a game will be placed into a suitableplace in the flash memory 324 of the device 300. The operating system ofthe device 300 will also allow for appropriate access to the newapplication as downloaded.

Exemplary embodiments have been described hereinabove regarding handheldelectronic devices 300 and wireless handheld communication devices 300as well as the communication networks within which they cooperate. Itshould be appreciated, however, that a focus of the present disclosureis the enablement of a keyboard for a handheld electronic device withflexible keys to prevent or minimize typing errors due to finger overlapwith multiple keys.

1. A wireless handheld mobile communication device having a keypadarrangement configured for minimizing typing errors when an intended keyand an adjacent key are engaged at substantially the same time by atypist because of finger overlap, the device comprising: a housingconfigured to be cradled in a palm of a user's hand and having a displaylocated in a top portion thereof for displaying information to the userand a keypad arrangement exposed for user actuation below the display,the keypad arrangement comprising: a support frame face upon which aplurality of depressible typing keys are mounted and each of the keys ismoveable between actuated and unactuated positions wherein the actuatedposition is closer to the support frame face than the unactuatedposition; each of the keys having a plurality of actuatorsinterconnected to a body of the key at a position toward the supportframe face from the key body and each of the plurality of actuatorsbeing moveable with the key body between actuated and unactuatedpositions wherein the actuated position is closer to the support frameface than the unactuated position and each of the actuators is biasedtoward the unactuated position; and each of the plurality of actuatorsinterconnected to a particular key body being spaced apart, one from theothers, and the key body comprising a flexible portion between theplurality of actuators, the flexible portion being sufficiently flexibleto allow one actuator to be in the actuated position while at least oneof the other of the plurality of actuators on that key body is in theunactuated position.
 2. The wireless handheld mobile communicationdevice as recited in claim 1, wherein the device has a width greaterthan fifty millimeters and less than eighty-nine millimeters therebyfacilitating user palm-cradling of the device.
 3. The wireless handheldmobile communication device as recited in claim 1, wherein the pluralityof actuators interconnected to the particular key body arecircumferentially apart about a centerpoint of the key body at aninterval approximately equal to 360 degrees divided by the number ofactuators constituting the plurality of actuators interconnected to theparticular key body.
 4. The wireless handheld mobile communicationdevice as recited in claim 1, wherein two actuators are interconnectedto the particular key body and are circumferentially apart about acenterpoint of the key body at an interval of approximately 180 degrees.5. The wireless handheld mobile communication device as recited in claim4, further comprising an actuator and a closeable switch capable ofproviding tactile feedback positioned at a centerpoint of the particularkey body.
 6. The wireless handheld mobile communication device asrecited in claim 4, wherein the key body is substantially rectangular inshape and the two actuators are located at opposite corners of the keybody.
 7. The wireless handheld mobile communication device as recited inclaim 6, wherein, for each actuator located at the corner of the keybody, the portion of the key body to which the particular actuator isinterconnected is more stiff than the flexible portion of the key body.8. The wireless handheld mobile communication device as recited in claim1, wherein four actuators are interconnected to the particular key bodyand are circumferentially apart about a centerpoint of the key body atan interval of approximately 90 degrees.
 9. The wireless handheld mobilecommunication device as recited in claim 8, further comprising anactuator and a closeable switch capable of providing tactile feedbackpositioned at a centerpoint of the particular key body.
 10. The wirelesshandheld mobile communication device as recited in claim 8, wherein thekey body is substantially rectangular in shape and the four actuatorsare located in corners of the key body.
 11. The wireless handheld mobilecommunication device as recited in claim 10, wherein, for each actuatorlocated at the corner of the key body, the portion of the key body towhich the particular actuator is interconnected is more stiff than theflexible portion of the key body.
 12. The wireless handheld mobilecommunication device as recited in claim 1, further comprising: a serieselectrical circuit associated with each of the key bodies for detectingwhen an intended key is actuated, the series circuit comprising a numberof closeable switches equal to the number of actuators constituting theplurality of actuators interconnected to the particular key body, eachof the closeable switches being configured to be closed when engaged bya corresponding actuator.
 13. The wireless handheld mobile communicationdevice as recited in claim 1, further comprising: a series electricalcircuit associated with each of the key bodies for detecting when anintended key is actuated, the series circuit comprising a number ofcloseable switches equal to the number of actuators constituting theplurality of actuators interconnected to the particular key body, eachof the closeable switches being configured to be closed when acorresponding actuator is in the actuated position.
 14. The wirelesshandheld mobile communication device as recited in claim 1, wherein eachkey body has an exposed finger-engageable surface having a width of lessthan seven millimeters.
 15. The wireless handheld mobile communicationdevice as recited in claim 1, wherein each key body has an exposedfinger-engageable surface having a width of approximately threemillimeters.
 16. The wireless handheld mobile communication device asrecited in claim 1, wherein said device is capable of wireless voicecommunication and wireless data communication.
 17. The wireless handheldmobile communication device as recited in claim 1, wherein saidplurality of keys have letter indicia arranged in a QWERTY formatassociated therewith.
 18. The wireless handheld mobile communicationdevice as recited in claim 1, further comprising an auxiliary inputdevice located substantially between said display and said keypadarrangement.
 19. The wireless handheld mobile communication device asrecited in claim 1, further comprising an auxiliary input device locatedsubstantially between said display and said keypad arrangement, saidauxiliary input device being a trackball arrangement.
 20. The wirelesshandheld mobile communication device as recited in claim 1, furthercomprising an auxiliary input device located substantially between saiddisplay and said keypad arrangement, said auxiliary input device being anavigation key.
 21. The wireless handheld mobile communication device asrecited in claim 1, further comprising an auxiliary input device locatedsubstantially between said display and said keypad arrangement, saidauxiliary input device being a navigation wheel.
 22. The wirelesshandheld mobile communication device as recited in claim 1, furthercomprising an auxiliary input device located substantially between saiddisplay and said keypad arrangement, said auxiliary input device beingcursor keys.
 23. The wireless handheld mobile communication device asrecited in claim 1, further comprising an auxiliary input device, saidauxiliary input device being a track wheel.
 24. The wireless handheldmobile communication device as recited in claim 1, further comprising anauxiliary input device located substantially between said display andsaid keypad arrangement, said auxiliary input device being a rollerbarrel.
 25. The wireless handheld mobile communication device as recitedin claim 1, further comprising an auxiliary input device locatedsubstantially between said display and said keypad arrangement, saidauxiliary input device being a touch pad.
 26. The wireless handheldmobile communication device as recited in claim 1, further comprising anauxiliary input device located substantially between said display andsaid keypad arrangement, said auxiliary input device being a joystick.27. A keypad arrangement configured for minimizing typing errors when anintended key and an adjacent key are engaged at substantially the sametime by a typist because of finger overlap, the keypad arrangementcomprising: a support frame face upon which a plurality of depressibletyping keys are mounted and each of the keys is moveable betweenactuated and unactuated positions wherein the actuated position iscloser to the support frame face than the unactuated position; each ofthe keys having a plurality of actuators interconnected to a body of thekey at a position toward the support frame face from the key body andeach of the plurality of actuators being moveable with the key bodybetween actuated and unactuated positions wherein the actuated positionis closer to the support frame face than the unactuated position andeach of the actuators is biased toward the unactuated position; and eachof the plurality of actuators interconnected to a particular key bodybeing spaced apart, one from the others, and the key body comprising aflexible portion between the plurality of actuators, the flexibleportion being sufficiently flexible to allow one actuator to be in theactuated position while at least one of the other of the plurality ofactuators on that key body is in the unactuated position.
 28. Thearrangement as recited in claim 27, wherein the plurality of actuatorsinterconnected to the particular key body are circumferentially apartabout a centerpoint of the key body at an interval approximately equalto 360 degrees divided by the number of actuators constituting theplurality of actuators interconnected to the particular key body. 29.The arrangement as recited in claim 27, wherein two actuators areinterconnected to the particular key body and are circumferentiallyapart about a centerpoint of the key body at an interval ofapproximately 180 degrees.
 30. The arrangement as recited in claim 29,further comprising an actuator and a closeable switch capable ofproviding tactile feedback positioned at the centerpoint of theparticular key body.
 31. The arrangement as recited in claim 29, whereinthe key body is substantially rectangular in shape and the two actuatorsare located at opposite corners of the key body.
 32. The arrangement asrecited in claim 31, wherein, for each actuator located at the corner ofthe key body, the portion of the key body to which the particularactuator is interconnected is more stiff than the flexible portion ofthe key body.
 33. The arrangement as recited in claim 27, wherein fouractuators are interconnected to the particular key body and arecircumferentially apart about a centerpoint of the key body at aninterval of approximately 90 degrees.
 34. The arrangement as recited inclaim 33, further comprising an actuator and a closeable switch capableof providing tactile feedback positioned at a centerpoint of theparticular key body.
 35. The arrangement as recited in claim 33, whereinthe key body is substantially rectangular in shape and the fouractuators are located in corners of the key body.
 36. The arrangement asrecited in claim 35, wherein, for each actuator located at the corner ofthe key body, the portion of the key body to which the particularactuator is interconnected is more stiff than the flexible portion ofthe key body.
 37. The arrangement as recited in claim 27, furthercomprising: a series electrical circuit associated with each of the keybodies for detecting when an intended key is actuated, the seriescircuit comprising a number of closeable switches equal to the number ofactuators constituting the plurality of actuators interconnected to theparticular key body, each of the closeable switches being configured tobe closed when engaged by a corresponding actuator.
 38. The arrangementas recited in claim 27, further comprising: a series electrical circuitassociated with each of the key bodies for detecting when an intendedkey is actuated, the series circuit comprising a number of closeableswitches equal to the number of actuators constituting the plurality ofactuators interconnected to the particular key body, each of thecloseable switches being configured to be closed when a correspondingactuator is in the actuated position.
 39. The arrangement as recited inclaim 27, wherein each key body has an exposed finger-engageable surfacehaving a width of less than seven millimeters.
 40. The arrangement asrecited in claim 27, wherein each key body has an exposedfinger-engageable surface having a width of approximately threemillimeters.